docs: def integrate(self, wave=None):
          """Integrate the throughput over the specified wavelength set.
          If no wavelength set is specified, the built-in one is used.
  
          Integration is done using :meth:`~Integrator.trapezoidIntegration`
          with ``x=wave`` and ``y=throughput``.
          Also see :ref:`pysynphot-formula-equvw`.
  
          Parameters
          ----------
          wave : array_like or `None`
              Wavelength set for integration.
  
          Returns
          -------
          ans : float
              Integrated sum.
  
          """
  
          if wave is None:
              wave = self.wave
          ans = self.trapezoidIntegration(wave, self(wave))
          return ans